A drilling liner can be carried along behind the pilot bit to line a borehole while it is being drilled. Previously drilling fluid has been circulated down through a drill pipe, through the pilot bit and up the outer annulus between the drilling liner and the borehole wall. In these previous methods, drilling with a liner was often difficult. Pressure exerted on the formation due to a combination of the fluid density and the frictional pressure losses in the small annulus between the liner and the borehole/casing wall may induce fractures in the formation and cause lost circulation.
Alternately, in other methods, the drilling fluid is circulated down through the drill pipe and forced up through the liner by sealing between the liner shoe and the borehole wall. This requires the use of an open hole packer, which may not be desirable.